1. Field of the Invention
The present invention relates to a substrate processing apparatus for performing a predetermined process in a substrate manufacturing operation and the like. More particularly, the invention relates to a technique for holding and releasing a substrate in such a substrate processing apparatus.
2. Description of the Background Art
A substrate processing apparatus for performing a predetermined process on a substrate (or a wafer), such as a coater for applying a processing solution onto a substrate and various inspection apparatuses for inspecting processing in a manufacturing operation for propriety, involves the need to fix the substrate in a predetermined position or to hold the substrate so as to securely transport the substrate. Conventionally, there has been proposed a substrate holding device for holding a substrate on a plate by means of a wafer suction mechanism for vacuum-holding the substrate in such cases. Such a substrate holding device is configured to cause the wafer suction mechanism to stop the atmosphere suction to thereby release the substrate when transporting the substrate from the plate which holds the substrate.
Unfortunately, the conventional substrate holding device presents a problem in that at the instant when the atmosphere suction is stopped, a backflow of atmosphere from the wafer suction mechanism takes place to blow particles in a pipe together with air against the substrate. Deposition of the particles on the substrate due to the backflow becomes a cause of reduction in yields of products.